Feline skull injuries: Treatment goals and recommended approaches.

PRACTICAL RELEVANCE: Skull trauma in cats, which includes fractures of the mandible and maxilla, as well as temporomandibular joint (TMJ) conditions, is frequently encountered in general practice. CLINICAL APPROACH: Head trauma requires immediate attention and the initial approach should be focused on stabilisation of the patient and evaluation of the major body systems, including respiratory and cardiovascular assessment, and neurological and ophthalmic examination. The head, oral occlusion and the patient's ability to open and close the mouth should be carefully evaluated. Once the cat is stable enough for anaesthesia, diagnostic imaging is essential to assess for skull injuries. Radiography may be helpful, although some conditions may be difficult to visualise due to soft tissue and bony structure superimposition. CT is a more sensitive technique for detecting skull injuries. TREATMENT GOALS AND TECHNIQUES: A variety of stabilisation techniques have been described in the feline patient, and repair goals focus on restoration of the animal's oral function, while ensuring adequate dental occlusion, minimal invasiveness and morbidity, and pain relief. Surgical repair of mandibular and maxillary fractures may variously involve interdental wiring, interarcade wiring or suture, use of interfragmentary wires, plate and screw fixation, external skeletal fixation and use of dental acrylic. Decision-making with regard to treatment options depends on dental occlusion, type and location of the fracture, fracture stability and pain. AIM: This review, directed at general practitioners working with cats, describes the relevant anatomy of the feline skull, the most common mandibular, maxillary and TMJ conditions, and their recommended management.

Maxillomandibular circular external skeletal fixation for repair of bilateral fractures of the caudal aspect of the mandible in a dog.

OBJECTIVE: To describe the novel use of circular external skeletal fixation (CESF) for repair of bilateral fractures of the caudal aspect of the mandibles. STUDY DESIGN: Clinical report. ANIMALS: A 5-month-old female Newfoundland. METHODS: A 2-ring CESF was used to immobilize the mandible relative to the maxillae. RESULTS: Anatomic dental occlusion and reduction of the right hemimandible were achieved with mild malalignment of the left hemimandible. Fracture healing occurred within 20 days. Transient epistaxis and reduced temporomandibular joint range of motion occurred at the time of fixator removal but normal use of the mandible was reported 6 months postoperatively. CONCLUSIONS: CESF effectively immobilized the mandible permitting rapid fracture healing with minimal morbidity. CLINICAL RELEVANCE: Maxillomandibular CESF may represent a simple, effective option for the management of challenging fractures involving the caudal aspect of the mandible.

Mandibular reconstruction after gunshot trauma in a dog by use of recombinant human bone morphogenetic protein-2.

CASE DESCRIPTION: A 6-year-old German Shorthaired Pointer was evaluated for possible reconstruction of a mandibular defect resulting from gunshot trauma. CLINICAL FINDINGS: A 5-cm defect of the right mandibular body was evident. A segment of the mandibular body was removed 9 weeks earlier because of severe contamination and comminution associated with gunshot trauma. Subsequent right-sided mandibular drift resulted in malocclusion in which the left mandibular canine tooth caused trauma to mucosa of the hard palate medial to the left maxillary canine tooth. The right maxillary canine tooth caused trauma to gingiva lingual to the right mandibular canine tooth. TREATMENT AND OUTCOME: The right mandible was stabilized with a 2.0-mm maxillofacial miniplate positioned along the lateral alveolar margin and a 2.4-mm locking mandibular reconstruction plate placed along the ventrolateral mandible. An absorbable compression-resistant matrix containing collagen, hydroxyapatite, and tricalcium phosphate was soaked in recombinant human bone morphogenetic protein-2 (rhBMP-2; 7.2 mL of a 0.5 mg/mL solution for a dose of 3.6 mg) and placed in the defect. By 4 weeks after surgery, an exuberant callus was evident at the site of the defect. By 7 months after surgery, the callus had remodeled, resulting in normal appearance, normal occlusion, and excellent function of the jaw. CLINICAL RELEVANCE: Mandibular defects resulting from gunshot trauma can be treated by removal of contaminated tissue and comminuted bone fragments, followed by staged reconstruction. The combination of rhBMP-2 and compression-resistant matrix was effective in a staged mandibular reconstruction in a dog with a severe traumatic mandibular defect.

Equine dental disease. Part 3: A long-term study of 400 cases: disorders of wear, traumatic damage and idiopathic fractures, tumours and miscellaneous disorders of the cheek teeth.

Of 400 horses referred because of dental disorders, 349 cases were diagnosed as suffering from primary disorders of their cheek teeth. Details of 104 of these cases are presented, including 44 cases with abnormalities of wear, 26 cases with traumatic damage, 24 cases with idiopathic fractures and 10 cases with miscellaneous cheek teeth disorders including oral tumours. The long-term response to treatment was excellent in most cases, even in cases with residual secondary periodontal disease.

Dental and mandibular injury in an Antarctic fur seal, Arctocephalus gazella, at Heard Island, Southern Ocean.

The skull of an adult male Antarctic fur seal (Arctocephalus gazella) collected at Heard Island, Southern Ocean, October 1992, had chronic changes attributable to a fracture of the left lower canine, luxation of the mental symphysis, osteomyelitis of the left and right mandibles, and periostitis of the left maxilla.

Repair of labial avulsion in a cat.

This photo essay illustrates a technique used for treating a cat presented with a trauma induced detachment of the labial mucosa. Stainless steel orthopedic wire was placed through the mandible to effect reattachment of the labial avulsion.

Field recovery and analysis of horse skeletal remains.

In response to a request from an insurance company investigating a claim relative to the death of four race and show horses, allegedly as a result of deliberate starvation, physical anthropologists of the Louisiana State University (LSU) Department of Geography and Anthropology undertook the recovery and analysis of skeletal remains said to be those of the animals. The objectives were to determine the number and kinds of animals represented, their ages, and sexes, and, through morphometric evaluation of bone density at the LSU School of Veterinary Medicine, whether there was evidence of nutritional osteodystrophy. The skeletons were the remains of four horses. In comparisons of data derived from these skeletons with breeding records for the horses described in the insurance claim, it was established that the skeletons were those of mares, as were the insured animals, and that the relative ages of the four approximated those of the insured horses. The skeletal samples submitted for morphometric evaluation showed no evidence of nutritional osteodystrophy and, thus, provided no support for the contention that death had resulted from starvation. In one horse, the superior aspect of the right ascending ramus of the lower jaw below the coronoid process revealed a gunshot wound; the other skeletons showed no evidence of trauma.

Mandibular lesions in the Western Arctic caribou herd of Alaska.

Lesions were noted in 7.0 and 4.4% of mandible pairs collected from the Western Arctic caribou herd of northwestern Alaska in 1959-61 and 1975-77, respectively. The prevalence of mandibular lesions in the 1959-61 collection is believed to be the highest reported in wild caribou herds of North America. The frequency of occurrence of mandibular lesions was highest in caribou 7 years of age and older, and there was a higher prevalence in adult males than in adult females. Trauma, dental abscesses, and periodontal disease were the probably cause of most lesions. Pathogenic bacteria were not isolated from mandibular lesions from an 11 year-old female. Thirty-three of 98 (33.7%) mandibles with lesions were missing one tooth, while ten (10.2%) were missing more than one tooth. The first molar (M1) was the most common tooth lost in association with lesions, although the loss of two or more teeth was more common among premolars than among molars.

Radiographic examination of mandibular lesions in barren-ground caribou.

Dental anomalies were observed in 43 of 1,226 barren-ground caribou (Rangifer tarandus groenlandicus) taken between 1966 and 1968. In five of these 43 animals, the mandibles had deformities which radiography showed to be the result of dental abscesses in four cases and probably of a trauma in the other. The absence of actinomycotic lesions of the jaw bones of these 1,226 animals, and of more than 500 examined previously, indicates that "lumpy jaw" is rare in barren-ground caribou. The authors suggest the use of radiography to determine the nature of bone growth on skeletal remains, in the absence of soft tissues for examination for Actinomyces, either microscopically or by cultural methods.